Improvement in dress for millstones



J. H. WELCH & E. P. HANN.

DRESS FOR MILLSTONES.

No.178,8Z0. Patented'June13,1876,.

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- from the periphery to the center.

JAMES H. WELOH AND EDMOND P.. HANN, OF GEORGETOWN, DISTRIGT OF A STATESPATENT QFFIGE.

COLUMBIA, ASSIGNORS OF PART OF THEIR RIGHT TO It. W. VVELOH AND E. P.WELOH, OF SAME PLACE.

IMPROVEMENT lN DRESS I-"OR MILLSTONES.

Specification forming part of Letters Patent N 0. 178,820, dated June13, 1876, application filed May 24, 1876. I

To all whom it'mag] concern Be it known that I, JAMES H. WELCII andEDMOND P. HANN, of Georgetown, in the county of Washington and Districtof Columbia, have invented certain Improvements in Dress forMillstones,of which the following is a specification: Our inventionconsists of. a novel dress for millstones, in which a portion of thelands of the grinding-face of the stone is dressed off or made lowerthan the other portions, as and for the purpose hereinafter set forth.

Figure l is a plan or face view of a lower millstone on our plan. Fig. 2is a side elevation of the same, shown partly in section, as indicatedby the line a: a; of Fig. 1; and Fig. 3 is a sectional elevationenlarged, to more clearly illustrate the invention.

Since the introduction of middlings-purifiers, or machines for theseparation of the middlings from the shorts and other materials, wherebythe middlin gs can be cleaned and used as flour, it has becomedesirable, in the grinding of the grain, to produce a larger yield orproportion of the middlings, and it is to accomplish this object thatour invention is designed; and to this end it consists in so dressingthe stone that portions of the grindingsurface, or, as they aretechnically termed, the Hands, shall be lower than others, therebyaffording an opportunity or space for the middlin gs to escape, and thusprevent their being ground into fine flour.

This dress may be applied to either the upper or lower stone, but as, ingrinding, the

meal or ground material rests on the surface of the lower stone, it isobviously better to apply the dress to the lower stone; and'we have,therefore, shown it so applied in the drawings.

In Fig. 1 the face of the stone is shown divided into a series of longand short lands the longer lands 0 extending from the periphcry to thecenter, or near the center, while the shorter lands a extend only abouthalf-way The longer lands 6 are dressed to a uniform height, while theshorter lands a, as shown in Figs. 2 and to 'millers.

3, are so dressed as to make their surface somewhat lower than that ofthe lands 6. As these lands a extend only about half-way to the center,it will be seen that about one-half of the diameter of the face of thestone, or a .little more, is composed entirely of the higher lands 6,while the remaining portion is composed of alternate high and low lands.The result of such a construction or dress is that the grain, as it isfed in at the center, is first crushed upon the central portion of thehigher lands 6, while the middlings, as they are separated from thebran, &c., fall upon the lower lands a, from which they are dischargedcentrifugally, without being further pulverized or converted into fineflour. At the same time, the bran, being of a different form, is carriedon across the face of the lands 0, and is thereby thoroughly cleaned ofthe adhering particles of flour. As .shown in the drawings, thelands areseparated by intervening furrows 0 in the usual manner. The differencein height between the lands a and 6 should be such that while themiddlings, while lying on the lands a, shall not be crushed or furtherground, there shall not be room for any unbroken kernels to escapewithout being ground.

When the dress is thus applied to the lower or bed stonethe-upper stone,or runner, should be dressed with its lands of uniform height, in theusual manner. It is, however, obvious that both the upper and lowerstones may be thus dressed with high and low lands; but in that casethere should be buthalf the difference between the height of the landsin the respective stones; but we do not consider this plan as good, forthe obvious reason that the middlings would be ground more, andtherefore the desired resultwould be less perfectly accomplished. 1

We do not confine ourselves to any particular style of dress other thanthat of the high and low lands, as it is obvious that our invention maybe applied with any of the various styles of dress, of which many kindsare known Neither is it necessary that the high and low lands shouldalternate or be arranged in the special order shown; nor that theyshould occupy the exact proportions of surface shown, these beingmatters to be determined by practical experiment and test.

Havingthus described our invention, what we claim is 1. A millstonehaving that portion of its face upon which the grain is ground after ithas been crushed at the center composed of e I series of lands the facesof which shall stand at difierent heights, substantially as and for thepurpose set forth.

2. The combination, in a millstone, of the higher lands 0 and the loweror depressed lands a, substantially as set forth.

JAMES H. WELOH. EDMOND P. HANN.

Witnesses:

JOHN D. NEWMAN, GEO. H. BRADY.

